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Peter Meerwald474fe212014-02-05 16:57:00 +00001/*
2 * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
3 *
4 * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +01005 * Copyright (c) 2015 Essensium NV
Crt Mori764589b2015-08-17 19:34:33 +02006 * Copyright (c) 2015 Melexis
Peter Meerwald474fe212014-02-05 16:57:00 +00007 *
8 * This file is subject to the terms and conditions of version 2 of
9 * the GNU General Public License. See the file COPYING in the main
10 * directory of this archive for more details.
11 *
12 * Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
13 *
14 * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
15 *
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +020016 * To wake up from sleep mode, the SDA line must be held low while SCL is high
17 * for at least 33ms. This is achieved with an extra GPIO that can be connected
18 * directly to the SDA line. In normal operation, the GPIO is set as input and
19 * will not interfere in I2C communication. While the GPIO is driven low, the
20 * i2c adapter is locked since it cannot be used by other clients. The SCL line
21 * always has a pull-up so we do not need an extra GPIO to drive it high. If
22 * the "wakeup" GPIO is not given, power management will be disabled.
23 *
Peter Meerwald474fe212014-02-05 16:57:00 +000024 */
25
26#include <linux/err.h>
27#include <linux/i2c.h>
28#include <linux/module.h>
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +020029#include <linux/delay.h>
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +020030#include <linux/jiffies.h>
31#include <linux/gpio/consumer.h>
32#include <linux/pm_runtime.h>
Peter Meerwald474fe212014-02-05 16:57:00 +000033
34#include <linux/iio/iio.h>
Crt Mori764589b2015-08-17 19:34:33 +020035#include <linux/iio/sysfs.h>
Peter Meerwald474fe212014-02-05 16:57:00 +000036
Vianney le Clément de Saint-Marcq209c0062015-03-24 16:54:14 +010037#define MLX90614_OP_RAM 0x00
38#define MLX90614_OP_EEPROM 0x20
39#define MLX90614_OP_SLEEP 0xff
Peter Meerwald474fe212014-02-05 16:57:00 +000040
41/* RAM offsets with 16-bit data, MSB first */
Vianney le Clément de Saint-Marcq209c0062015-03-24 16:54:14 +010042#define MLX90614_RAW1 (MLX90614_OP_RAM | 0x04) /* raw data IR channel 1 */
43#define MLX90614_RAW2 (MLX90614_OP_RAM | 0x05) /* raw data IR channel 2 */
Vianney le Clément de Saint-Marcqc7586582015-02-25 16:55:06 +010044#define MLX90614_TA (MLX90614_OP_RAM | 0x06) /* ambient temperature */
45#define MLX90614_TOBJ1 (MLX90614_OP_RAM | 0x07) /* object 1 temperature */
Vianney le Clément de Saint-Marcq209c0062015-03-24 16:54:14 +010046#define MLX90614_TOBJ2 (MLX90614_OP_RAM | 0x08) /* object 2 temperature */
47
48/* EEPROM offsets with 16-bit data, MSB first */
49#define MLX90614_EMISSIVITY (MLX90614_OP_EEPROM | 0x04) /* emissivity correction coefficient */
50#define MLX90614_CONFIG (MLX90614_OP_EEPROM | 0x05) /* configuration register */
51
52/* Control bits in configuration register */
53#define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
54#define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
55#define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
56#define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
57#define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
58#define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
59#define MLX90614_CONFIG_GAIN_SHIFT 11 /* gain */
60#define MLX90614_CONFIG_GAIN_MASK (0x7 << MLX90614_CONFIG_GAIN_SHIFT)
61
62/* Timings (in ms) */
63#define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
64#define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
65#define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
Peter Meerwald474fe212014-02-05 16:57:00 +000066
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +020067#define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
68
Crt Morif9ba1ab2015-07-20 21:38:27 +020069/* Magic constants */
70#define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
71#define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.15*50) */
72#define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
73#define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
74#define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */
Crt Mori1de953e2015-10-02 14:24:21 +020075#define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
Crt Morif9ba1ab2015-07-20 21:38:27 +020076
Peter Meerwald474fe212014-02-05 16:57:00 +000077struct mlx90614_data {
78 struct i2c_client *client;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +020079 struct mutex lock; /* for EEPROM access only */
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +020080 struct gpio_desc *wakeup_gpio; /* NULL to disable sleep/wake-up */
81 unsigned long ready_timestamp; /* in jiffies */
Peter Meerwald474fe212014-02-05 16:57:00 +000082};
83
Crt Mori764589b2015-08-17 19:34:33 +020084/* Bandwidth values for IIR filtering */
85static const int mlx90614_iir_values[] = {77, 31, 20, 15, 723, 153, 110, 86};
86static IIO_CONST_ATTR(in_temp_object_filter_low_pass_3db_frequency_available,
87 "0.15 0.20 0.31 0.77 0.86 1.10 1.53 7.23");
88
89static struct attribute *mlx90614_attributes[] = {
90 &iio_const_attr_in_temp_object_filter_low_pass_3db_frequency_available.dev_attr.attr,
91 NULL,
92};
93
94static const struct attribute_group mlx90614_attr_group = {
95 .attrs = mlx90614_attributes,
96};
97
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +020098/*
99 * Erase an address and write word.
100 * The mutex must be locked before calling.
101 */
102static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
103 u16 value)
104{
105 /*
106 * Note: The mlx90614 requires a PEC on writing but does not send us a
107 * valid PEC on reading. Hence, we cannot set I2C_CLIENT_PEC in
108 * i2c_client.flags. As a workaround, we use i2c_smbus_xfer here.
109 */
110 union i2c_smbus_data data;
111 s32 ret;
112
113 dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
114
115 data.word = 0x0000; /* erase command */
116 ret = i2c_smbus_xfer(client->adapter, client->addr,
117 client->flags | I2C_CLIENT_PEC,
118 I2C_SMBUS_WRITE, command,
119 I2C_SMBUS_WORD_DATA, &data);
120 if (ret < 0)
121 return ret;
122
123 msleep(MLX90614_TIMING_EEPROM);
124
125 data.word = value; /* actual write */
126 ret = i2c_smbus_xfer(client->adapter, client->addr,
127 client->flags | I2C_CLIENT_PEC,
128 I2C_SMBUS_WRITE, command,
129 I2C_SMBUS_WORD_DATA, &data);
130
131 msleep(MLX90614_TIMING_EEPROM);
132
133 return ret;
134}
135
Crt Mori764589b2015-08-17 19:34:33 +0200136/*
137 * Find the IIR value inside mlx90614_iir_values array and return its position
138 * which is equivalent to the bit value in sensor register
139 */
140static inline s32 mlx90614_iir_search(const struct i2c_client *client,
141 int value)
142{
143 int i;
144 s32 ret;
145
146 for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
147 if (value == mlx90614_iir_values[i])
148 break;
149 }
150
151 if (i == ARRAY_SIZE(mlx90614_iir_values))
152 return -EINVAL;
153
154 /*
155 * CONFIG register values must not be changed so
156 * we must read them before we actually write
157 * changes
158 */
159 ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
Crt Mori1de953e2015-10-02 14:24:21 +0200160 if (ret < 0)
Crt Mori764589b2015-08-17 19:34:33 +0200161 return ret;
162
Crt Mori1de953e2015-10-02 14:24:21 +0200163 ret &= ~MLX90614_CONFIG_FIR_MASK;
164 ret |= MLX90614_CONST_FIR << MLX90614_CONFIG_FIR_SHIFT;
165 ret &= ~MLX90614_CONFIG_IIR_MASK;
166 ret |= i << MLX90614_CONFIG_IIR_SHIFT;
167
Crt Mori764589b2015-08-17 19:34:33 +0200168 /* Write changed values */
Crt Mori1de953e2015-10-02 14:24:21 +0200169 ret = mlx90614_write_word(client, MLX90614_CONFIG, ret);
Crt Mori764589b2015-08-17 19:34:33 +0200170 return ret;
171}
172
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200173#ifdef CONFIG_PM
174/*
175 * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
176 * the last wake-up. This is normally only needed to get a valid temperature
177 * reading. EEPROM access does not need such delay.
178 * Return 0 on success, <0 on error.
179 */
180static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
181{
182 unsigned long now;
183
184 if (!data->wakeup_gpio)
185 return 0;
186
187 pm_runtime_get_sync(&data->client->dev);
188
189 if (startup) {
190 now = jiffies;
191 if (time_before(now, data->ready_timestamp) &&
192 msleep_interruptible(jiffies_to_msecs(
193 data->ready_timestamp - now)) != 0) {
194 pm_runtime_put_autosuspend(&data->client->dev);
195 return -EINTR;
196 }
197 }
198
199 return 0;
200}
201
202static void mlx90614_power_put(struct mlx90614_data *data)
203{
204 if (!data->wakeup_gpio)
205 return;
206
207 pm_runtime_mark_last_busy(&data->client->dev);
208 pm_runtime_put_autosuspend(&data->client->dev);
209}
210#else
211static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
212{
213 return 0;
214}
215
216static inline void mlx90614_power_put(struct mlx90614_data *data)
217{
218}
219#endif
220
Peter Meerwald474fe212014-02-05 16:57:00 +0000221static int mlx90614_read_raw(struct iio_dev *indio_dev,
222 struct iio_chan_spec const *channel, int *val,
223 int *val2, long mask)
224{
225 struct mlx90614_data *data = iio_priv(indio_dev);
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100226 u8 cmd;
Peter Meerwald474fe212014-02-05 16:57:00 +0000227 s32 ret;
228
229 switch (mask) {
230 case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
231 switch (channel->channel2) {
232 case IIO_MOD_TEMP_AMBIENT:
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100233 cmd = MLX90614_TA;
Peter Meerwald474fe212014-02-05 16:57:00 +0000234 break;
235 case IIO_MOD_TEMP_OBJECT:
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100236 switch (channel->channel) {
237 case 0:
238 cmd = MLX90614_TOBJ1;
239 break;
240 case 1:
241 cmd = MLX90614_TOBJ2;
242 break;
243 default:
244 return -EINVAL;
245 }
Peter Meerwald474fe212014-02-05 16:57:00 +0000246 break;
247 default:
248 return -EINVAL;
249 }
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100250
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200251 ret = mlx90614_power_get(data, true);
252 if (ret < 0)
253 return ret;
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100254 ret = i2c_smbus_read_word_data(data->client, cmd);
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200255 mlx90614_power_put(data);
256
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100257 if (ret < 0)
258 return ret;
Vianney le Clément de Saint-Marcqd02e0f82015-03-30 10:35:02 +0200259
260 /* MSB is an error flag */
261 if (ret & 0x8000)
262 return -EIO;
263
Peter Meerwald474fe212014-02-05 16:57:00 +0000264 *val = ret;
265 return IIO_VAL_INT;
266 case IIO_CHAN_INFO_OFFSET:
Crt Morif9ba1ab2015-07-20 21:38:27 +0200267 *val = MLX90614_CONST_OFFSET_DEC;
268 *val2 = MLX90614_CONST_OFFSET_REM;
Peter Meerwald474fe212014-02-05 16:57:00 +0000269 return IIO_VAL_INT_PLUS_MICRO;
270 case IIO_CHAN_INFO_SCALE:
Crt Morif9ba1ab2015-07-20 21:38:27 +0200271 *val = MLX90614_CONST_SCALE;
Peter Meerwald474fe212014-02-05 16:57:00 +0000272 return IIO_VAL_INT;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200273 case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200274 mlx90614_power_get(data, false);
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200275 mutex_lock(&data->lock);
276 ret = i2c_smbus_read_word_data(data->client,
277 MLX90614_EMISSIVITY);
278 mutex_unlock(&data->lock);
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200279 mlx90614_power_put(data);
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200280
281 if (ret < 0)
282 return ret;
283
Crt Morif9ba1ab2015-07-20 21:38:27 +0200284 if (ret == MLX90614_CONST_RAW_EMISSIVITY_MAX) {
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200285 *val = 1;
286 *val2 = 0;
287 } else {
288 *val = 0;
Crt Morif9ba1ab2015-07-20 21:38:27 +0200289 *val2 = ret * MLX90614_CONST_EMISSIVITY_RESOLUTION;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200290 }
291 return IIO_VAL_INT_PLUS_NANO;
Crt Mori764589b2015-08-17 19:34:33 +0200292 case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
293 FIR = 1024 */
294 mlx90614_power_get(data, false);
295 mutex_lock(&data->lock);
296 ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
297 mutex_unlock(&data->lock);
298 mlx90614_power_put(data);
299
300 if (ret < 0)
301 return ret;
302
303 *val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
304 *val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100) *
305 10000;
306 return IIO_VAL_INT_PLUS_MICRO;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200307 default:
308 return -EINVAL;
309 }
310}
311
312static int mlx90614_write_raw(struct iio_dev *indio_dev,
313 struct iio_chan_spec const *channel, int val,
314 int val2, long mask)
315{
316 struct mlx90614_data *data = iio_priv(indio_dev);
317 s32 ret;
318
319 switch (mask) {
320 case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
321 if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
322 return -EINVAL;
Crt Morif9ba1ab2015-07-20 21:38:27 +0200323 val = val * MLX90614_CONST_RAW_EMISSIVITY_MAX +
324 val2 / MLX90614_CONST_EMISSIVITY_RESOLUTION;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200325
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200326 mlx90614_power_get(data, false);
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200327 mutex_lock(&data->lock);
328 ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,
329 val);
330 mutex_unlock(&data->lock);
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200331 mlx90614_power_put(data);
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200332
Jonathan Cameronf2c714a2015-05-02 11:35:02 +0100333 return ret;
Crt Mori764589b2015-08-17 19:34:33 +0200334 case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
335 if (val < 0 || val2 < 0)
336 return -EINVAL;
337
338 mlx90614_power_get(data, false);
339 mutex_lock(&data->lock);
340 ret = mlx90614_iir_search(data->client,
341 val * 100 + val2 / 10000);
342 mutex_unlock(&data->lock);
343 mlx90614_power_put(data);
344
345 return ret;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200346 default:
347 return -EINVAL;
348 }
349}
350
351static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
Vianney le Clément de Saint-Marcq6069f472015-04-17 16:05:35 +0200352 struct iio_chan_spec const *channel,
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200353 long mask)
354{
355 switch (mask) {
356 case IIO_CHAN_INFO_CALIBEMISSIVITY:
357 return IIO_VAL_INT_PLUS_NANO;
Crt Mori764589b2015-08-17 19:34:33 +0200358 case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
359 return IIO_VAL_INT_PLUS_MICRO;
Peter Meerwald474fe212014-02-05 16:57:00 +0000360 default:
361 return -EINVAL;
362 }
363}
364
365static const struct iio_chan_spec mlx90614_channels[] = {
366 {
367 .type = IIO_TEMP,
368 .modified = 1,
369 .channel2 = IIO_MOD_TEMP_AMBIENT,
370 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
371 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
372 BIT(IIO_CHAN_INFO_SCALE),
373 },
374 {
375 .type = IIO_TEMP,
376 .modified = 1,
377 .channel2 = IIO_MOD_TEMP_OBJECT,
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200378 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
Crt Mori764589b2015-08-17 19:34:33 +0200379 BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
380 BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
Peter Meerwald474fe212014-02-05 16:57:00 +0000381 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
382 BIT(IIO_CHAN_INFO_SCALE),
383 },
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100384 {
385 .type = IIO_TEMP,
386 .indexed = 1,
387 .modified = 1,
388 .channel = 1,
389 .channel2 = IIO_MOD_TEMP_OBJECT,
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200390 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
Crt Mori764589b2015-08-17 19:34:33 +0200391 BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
392 BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100393 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
394 BIT(IIO_CHAN_INFO_SCALE),
395 },
Peter Meerwald474fe212014-02-05 16:57:00 +0000396};
397
398static const struct iio_info mlx90614_info = {
399 .read_raw = mlx90614_read_raw,
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200400 .write_raw = mlx90614_write_raw,
401 .write_raw_get_fmt = mlx90614_write_raw_get_fmt,
Crt Mori764589b2015-08-17 19:34:33 +0200402 .attrs = &mlx90614_attr_group,
Peter Meerwald474fe212014-02-05 16:57:00 +0000403 .driver_module = THIS_MODULE,
404};
405
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200406#ifdef CONFIG_PM
407static int mlx90614_sleep(struct mlx90614_data *data)
408{
409 s32 ret;
410
411 if (!data->wakeup_gpio) {
412 dev_dbg(&data->client->dev, "Sleep disabled");
413 return -ENOSYS;
414 }
415
416 dev_dbg(&data->client->dev, "Requesting sleep");
417
418 mutex_lock(&data->lock);
419 ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
420 data->client->flags | I2C_CLIENT_PEC,
421 I2C_SMBUS_WRITE, MLX90614_OP_SLEEP,
422 I2C_SMBUS_BYTE, NULL);
423 mutex_unlock(&data->lock);
424
425 return ret;
426}
427
428static int mlx90614_wakeup(struct mlx90614_data *data)
429{
430 if (!data->wakeup_gpio) {
431 dev_dbg(&data->client->dev, "Wake-up disabled");
432 return -ENOSYS;
433 }
434
435 dev_dbg(&data->client->dev, "Requesting wake-up");
436
437 i2c_lock_adapter(data->client->adapter);
438 gpiod_direction_output(data->wakeup_gpio, 0);
439 msleep(MLX90614_TIMING_WAKEUP);
440 gpiod_direction_input(data->wakeup_gpio);
441 i2c_unlock_adapter(data->client->adapter);
442
443 data->ready_timestamp = jiffies +
444 msecs_to_jiffies(MLX90614_TIMING_STARTUP);
445
446 /*
447 * Quirk: the i2c controller may get confused right after the
448 * wake-up signal has been sent. As a workaround, do a dummy read.
449 * If the read fails, the controller will probably be reset so that
450 * further reads will work.
451 */
452 i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
453
454 return 0;
455}
456
457/* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
458static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
459{
460 struct gpio_desc *gpio;
461
462 if (!i2c_check_functionality(client->adapter,
463 I2C_FUNC_SMBUS_WRITE_BYTE)) {
464 dev_info(&client->dev,
465 "i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
466 return NULL;
467 }
468
469 gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
470
471 if (IS_ERR(gpio)) {
472 dev_warn(&client->dev,
473 "gpio acquisition failed with error %ld, sleep disabled",
474 PTR_ERR(gpio));
475 return NULL;
476 } else if (!gpio) {
477 dev_info(&client->dev,
478 "wakeup-gpio not found, sleep disabled");
479 }
480
481 return gpio;
482}
483#else
484static inline int mlx90614_sleep(struct mlx90614_data *data)
485{
486 return -ENOSYS;
487}
488static inline int mlx90614_wakeup(struct mlx90614_data *data)
489{
490 return -ENOSYS;
491}
492static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
493{
494 return NULL;
495}
496#endif
497
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100498/* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
499static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
500{
501 s32 ret;
502
503 ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
504
505 if (ret < 0)
506 return ret;
507
508 return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
509}
510
Peter Meerwald474fe212014-02-05 16:57:00 +0000511static int mlx90614_probe(struct i2c_client *client,
512 const struct i2c_device_id *id)
513{
514 struct iio_dev *indio_dev;
515 struct mlx90614_data *data;
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100516 int ret;
Peter Meerwald474fe212014-02-05 16:57:00 +0000517
518 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
519 return -ENODEV;
520
521 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
522 if (!indio_dev)
523 return -ENOMEM;
524
525 data = iio_priv(indio_dev);
526 i2c_set_clientdata(client, indio_dev);
527 data->client = client;
Vianney le Clément de Saint-Marcqfad65a82015-03-30 10:35:00 +0200528 mutex_init(&data->lock);
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200529 data->wakeup_gpio = mlx90614_probe_wakeup(client);
530
531 mlx90614_wakeup(data);
Peter Meerwald474fe212014-02-05 16:57:00 +0000532
533 indio_dev->dev.parent = &client->dev;
534 indio_dev->name = id->name;
535 indio_dev->modes = INDIO_DIRECT_MODE;
536 indio_dev->info = &mlx90614_info;
537
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100538 ret = mlx90614_probe_num_ir_sensors(client);
539 switch (ret) {
540 case 0:
541 dev_dbg(&client->dev, "Found single sensor");
542 indio_dev->channels = mlx90614_channels;
543 indio_dev->num_channels = 2;
544 break;
545 case 1:
546 dev_dbg(&client->dev, "Found dual sensor");
547 indio_dev->channels = mlx90614_channels;
548 indio_dev->num_channels = 3;
549 break;
550 default:
551 return ret;
552 }
Peter Meerwald474fe212014-02-05 16:57:00 +0000553
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200554 if (data->wakeup_gpio) {
555 pm_runtime_set_autosuspend_delay(&client->dev,
556 MLX90614_AUTOSLEEP_DELAY);
557 pm_runtime_use_autosuspend(&client->dev);
558 pm_runtime_set_active(&client->dev);
559 pm_runtime_enable(&client->dev);
560 }
561
Peter Meerwald474fe212014-02-05 16:57:00 +0000562 return iio_device_register(indio_dev);
563}
564
565static int mlx90614_remove(struct i2c_client *client)
566{
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200567 struct iio_dev *indio_dev = i2c_get_clientdata(client);
568 struct mlx90614_data *data = iio_priv(indio_dev);
569
570 iio_device_unregister(indio_dev);
571
572 if (data->wakeup_gpio) {
573 pm_runtime_disable(&client->dev);
574 if (!pm_runtime_status_suspended(&client->dev))
575 mlx90614_sleep(data);
576 pm_runtime_set_suspended(&client->dev);
577 }
Peter Meerwald474fe212014-02-05 16:57:00 +0000578
579 return 0;
580}
581
582static const struct i2c_device_id mlx90614_id[] = {
583 { "mlx90614", 0 },
584 { }
585};
586MODULE_DEVICE_TABLE(i2c, mlx90614_id);
587
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200588#ifdef CONFIG_PM_SLEEP
589static int mlx90614_pm_suspend(struct device *dev)
590{
591 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
592 struct mlx90614_data *data = iio_priv(indio_dev);
593
594 if (data->wakeup_gpio && pm_runtime_active(dev))
595 return mlx90614_sleep(data);
596
597 return 0;
598}
599
600static int mlx90614_pm_resume(struct device *dev)
601{
602 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
603 struct mlx90614_data *data = iio_priv(indio_dev);
604 int err;
605
606 if (data->wakeup_gpio) {
607 err = mlx90614_wakeup(data);
608 if (err < 0)
609 return err;
610
611 pm_runtime_disable(dev);
612 pm_runtime_set_active(dev);
613 pm_runtime_enable(dev);
614 }
615
616 return 0;
617}
618#endif
619
620#ifdef CONFIG_PM
621static int mlx90614_pm_runtime_suspend(struct device *dev)
622{
623 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
624 struct mlx90614_data *data = iio_priv(indio_dev);
625
626 return mlx90614_sleep(data);
627}
628
629static int mlx90614_pm_runtime_resume(struct device *dev)
630{
631 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
632 struct mlx90614_data *data = iio_priv(indio_dev);
633
634 return mlx90614_wakeup(data);
635}
636#endif
637
638static const struct dev_pm_ops mlx90614_pm_ops = {
639 SET_SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
640 SET_RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
641 mlx90614_pm_runtime_resume, NULL)
642};
643
Peter Meerwald474fe212014-02-05 16:57:00 +0000644static struct i2c_driver mlx90614_driver = {
645 .driver = {
646 .name = "mlx90614",
Vianney le Clément de Saint-Marcqeb4b07d2015-03-30 10:35:01 +0200647 .pm = &mlx90614_pm_ops,
Peter Meerwald474fe212014-02-05 16:57:00 +0000648 },
649 .probe = mlx90614_probe,
650 .remove = mlx90614_remove,
651 .id_table = mlx90614_id,
652};
653module_i2c_driver(mlx90614_driver);
654
655MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
Vianney le Clément de Saint-Marcqbad4d1a2015-03-24 16:54:15 +0100656MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
Crt Mori764589b2015-08-17 19:34:33 +0200657MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
Peter Meerwald474fe212014-02-05 16:57:00 +0000658MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
659MODULE_LICENSE("GPL");